50995-74-9Relevant articles and documents
Constructing Cross-Linked Nanofibrous Scaffold via Dual-Enzyme-Instructed Hierarchical Assembly
Cortes, William,Zhang, Shijin,Zhang, Ye
, p. 6261 - 6267 (2020)
To explore the potential of step-by-step assembly in the fabrication of biological materials, we designed and synthesized two peptide-based molecules for enzyme-instructed hierarchical assembly. Upon the treatment of alkaline phosphatase, one molecule undergoes enzyme-instructed self-assembly forming uniformed nanofibers. The other one that can self-assemble into vesicles undergoes enzyme-induced transformation of self-assembly converting vesicles into irregular aggregates upon the treatment of carboxylesterase. Coadministration of two enzymes to a mixture of these two molecules in a stage-by-stage fashion leads to a physically knotted nanofibrous scaffold that is applicable as a nanostructured matrix for cell culture.
Selective and ratiometric fluorescent trapping and quantification of protein vicinal dithiols and in situ dynamic tracing in living cells
Huang, Chusen,Jia, Ti,Tang, Mengfang,Yin, Qin,Zhu, Weiping,Zhang, Chao,Yang, Yi,Jia, Nengqin,Xu, Yufang,Qian, Xuhong
, p. 14237 - 14244 (2014)
Protein vicinal dithiols play fundamental roles in intracellular redox homeostasis due to their involvement in protein synthesis and function through the reversible vicinal dithiol oxidation to disulfide. To provide quantitative information about the glob
Anti-hypochlorite, antioxidant, and catalytic activity of three polyphenol-rich super-foods investigated with the use of coumarin-based sensors
Starzak, Karolina,?wiergosz, Tomasz,Matwijczuk, Arkadiusz,Creaven, Bernadette,Podle?ny, Janusz,Karcz, Dariusz
, (2020)
The anti-hypochlorite activity of a?aí (Euterpe oleracea Mart.), goji (Lycium barbarum L.) and schisandra (Schisandra chinensis) fruit extracts were assessed by determining the reactive chlorine species (RCS)-scavenging ability of these three “super-food” berries. In addition, the aqueous extracts obtained were employed as both the media and the catalyst in a green chemistry approach to the synthesis of a coumarin-based fluorescence turn-off sensor, which was then used for anti-hypochlorite activity testing. The aqueous extracts were also assessed for total phenolic content (TPC), using the Folin–Ciocalteu method, and the antioxidant activity using the ABTS+? assay. Moreover, the main water-soluble polyphenolic constituents of the extracts were identified by the HPLC-PDA-ESI-MS technique. Among the extracts tested, a?aí demonstrated the highest anti-hypochlorite and antioxidant activities, while the highest TPC value was found for the goji extract. All extracts demonstrated modest catalytic activity as Knoevenagel condensation catalysts.
A water soluble fluorescent polymer as a dual colour sensor for temperature and a specific protein
Inal, Sahika,Koelsch, Jonas D.,Sellrie, Frank,Schenk, Joerg A.,Wischerhoff, Erik,Laschewsky, Andre,Neher, Dieter
, p. 6373 - 6381 (2013)
We present two thermoresponsive water soluble copolymers prepared via free radical statistical copolymerization of N-isopropylacrylamide (NIPAm) and of oligo(ethylene glycol) methacrylates (OEGMAs), respectively, with a solvatochromic 7-(diethylamino)-3-carboxy-coumarin (DEAC)-functionalized monomer. In aqueous solutions, the NIPAm-based copolymer exhibits characteristic changes in its fluorescence profile in response to a change in solution temperature as well as to the presence of a specific protein, namely an anti-DEAC antibody. This polymer emits only weakly at low temperatures, but exhibits a marked fluorescence enhancement accompanied by a change in its emission colour when heated above its cloud point. Such drastic changes in the fluorescence and absorbance spectra are observed also upon injection of the anti-DEAC antibody, attributed to the specific binding of the antibody to DEAC moieties. Importantly, protein binding occurs exclusively when the polymer is in the well hydrated state below the cloud point, enabling a temperature control on the molecular recognition event. On the other hand, heating of the polymer-antibody complexes releases a fraction of the bound antibody. In the presence of the DEAC-functionalized monomer in this mixture, the released antibody competitively binds to the monomer and the antibody-free chains of the polymer undergo a more effective collapse and inter-aggregation. In contrast, the emission properties of the OEGMA-based analogous copolymer are rather insensitive to the thermally induced phase transition or to antibody binding. These opposite behaviours underline the need for a carefully tailored molecular design of responsive polymers aimed at specific applications, such as biosensing.
A novel ratiometric probe based on rhodamine B and coumarin for selective recognition of Fe(III) in aqueous solution
Ge, Fei,Ye, Hui,Zhang, He,Zhao, Bao-Xiang
, p. 661 - 665 (2013)
We have developed a new ratiometric fluorescence probe based on rhodamine B and coumarin to monitor the Fe3+ with high sensitivity and selectivity. Upon addition of Fe3+ to aqueous solution of the probe, two fluorescence peaks at 580 nm and 460 nm were observed, which belong to rhodamine B and coumarin, respectively. This is a novelty design of ratiometric probe of Fe3+, due to CHEF process generated along with the PET process suppressed simultaneously. The fluorescence intensity at 580 nm was significantly increased about 120-fold with 5 equiv. of Fe3+ added in aqueous solution.
Anti-hypochlorite and catalytic activity of commercially available moringa oleifera diet supplement
Starzak, Karolina,Creaven, Bernadette,Matwijczuk, Arkadiusz,Matwijczuk, Alicja,Karcz, Dariusz
, (2019)
Aiming at the assessment of the pro-health, and especially anti-hypochlorite properties of Moringa oleifera species a representative, commercially available Moringa oleifera dietary supplement was used as a substrate for the preparation of aqueous Moringa extract. The anti-hypochlorite activity of the extract was assessed using the hypochlorite-specific coumarin-based fluorescence turn-off sensor, namely 7-diethylamino-coumarin-3-carboxylic acid (7-DCCA). This compound was synthesized via the Knoevenagel condensation of 4-diethylamino-2-hydroxybenzaldehyde with Meldrum’s acid and the Moringa extract was employed as a medium and catalyst. Moreover, the total phenolic content (TPC) as well as the reactive oxygen species (ROS)–scavenging ability of the aqueous Moringa extract were determined. The results obtained demonstrated the applicability of Moringa extract as an anti-hypochlorite agent. Additionally, the satisfactory yield of the 7-DCCA obtained suggests the usefulness of the extract as a catalyst and the reaction medium. The antioxidative potential of the extract was notably lower than that of the standard (TROLOX). Determination of TPC in 100 g of the dry weight (DW) of studied material revealed a high number of polyphones present.
2-Benzoylpyridine Ligand Complexation with Gold Critical for Propargyl Ester-Based Protein Labeling
Lin, Yixuan,Vong, Kenward,Matsuoka, Koji,Tanaka, Katsunori
, p. 10595 - 10600 (2018)
In previously reported work, AuIII complexes coordinated with 2-benzoylpyridine ligand, BPy-Au, were prebound to a protein and used to discover a novel protein-directed labeling approach with propargyl ester functional groups. In this work, further examination discovered that gold catalysts devoid of the 2-benzoylpyridine ligand (e.g., NaAuCl4) had significantly reduced levels of protein labeling. Mechanistic investigations then revealed that BPy-Au and propargyl esters undergo a rare example of C(sp2)?C(sp) aryl–alkynyl cross-coupling, likely through spontaneous reductive elimination. Overall, these observations appear to suggest that BPy-Au-mediated, propargyl ester-based protein labeling acts via an activated ester intermediate, which contributes to our understanding of this process and will aid the expansion/optimization of gold-catalyst usage in future bioconjugation applications, especially in vivo.
Dual Mechanism of an Intramolecular Charge Transfer (ICT)–FRET-Based Fluorescent Probe for the Selective Detection of Hydrogen Peroxide
Liang, Xiao,Xu, Xiaoyi,Qiao, Dan,Yin, Zheng,Shang, Luqing
, p. 3187 - 3194 (2017)
A dual-mechanism intramolecular charge transfer (ICT)–FRET fluorescent probe for the selective detection of H2O2 in living cells has been designed and synthesized. This probe used a coumarin–naphthalimide hybrid as the FRET platform and a boronate moiety as the recognition group. Upon the addition of H2O2, the probe exhibited a redshifted (73 nm) fluorescence emission, and the ratio of fluorescence intensities at λ=558 and 485 nm (F558/F485) shifted notably (up to 100-fold). Moreover, there was a good linearity (R2=0.9911) between the ratio and concentration of H2O2 in the range of 0 to 60 μm, with a limit of detection of 0.28 μm (signal to noise ratio (S/N)=3). This probe could also detect enzymatically generated H2O2. Importantly, it could be used to visualize endogenous H2O2 produced by stimulation from epidermal growth factor.
Highly Polarized Coumarin Derivatives Revisited: Solvent-Controlled Competition Between Proton-Coupled Electron Transfer and Twisted Intramolecular Charge Transfer
Gryko, Daniel T.,Kielesiński, ?ukasz,Morawski, Olaf W.,Sobolewski, Andrzej L.
, (2020)
Linking a polarized coumarin unit with an aromatic substituent via an amide bridge results in weak electronic coupling that affects the intramolecular electron-transfer (ET) process. As a result of this, interesting solvent-dependent photophysical properties can be observed. In polar solvents, electron transfer in coumarin derivatives of this type induces a mutual twist of the electron-donating and -accepting molecular units (TICT process) that facilitates radiationless decay processes (internal conversion). In the dyad with the strongest intramolecular hydrogen bond, the planar form is stabilized, such that twisting can only occur in highly polar solvents, whereas a fast proton-coupled electron-transfer (PCET process) occurs in nonpolar n-alkanes. The kPCET rate constant decreases linearly with the energy of the fluorescence maximum in different solvents. This observation can be explained in terms of competition between electron- and proton-transfer from a highly polarized (ca. 15 D) and fluorescent locally excited (1LE) state to a much less polarized (ca. 4 D) charge-transfer (1CT) state, a unique occurrence. Photophysical measurements performed for a family of related coumarin dyads, together with results of quantum-chemical computations, give insight into the mechanism of the ET process, which is followed by either a TICT or a PCET process. Our results reveal that dielectric solvation of the excited state slows down the PCET process, even in nonpolar solvents.
Accurately selected 1,3,4-thiadiazole and coumarin unit to construct fluorescent probes that effectively detect 2,4,6-trinitrophenol
An, Yue,Gao, Ge,Lü, Chengwei,Li, Xuejiao
supporting information, (2022/01/14)
Two remarkablely fluorimetric probes were developed to rapidly detect 2,4,6-trinitrophenol (TNP). With the help of density functional theory (DFT) calculations, we confirmed that using 1,3,4-thiadiazole skeleton as recognition group and coumarin unit as f
Spatially Confined Intervention of Cellular Senescence by a Lysosomal Metabolism Targeting Molecular Prodrug for Broad-Spectrum Senotherapy
Li, Jili,Liu, Yanlan,Luo, Xiyuan,Wang, Linlin,Xia, Yinghao,Xie, Yuqi
supporting information, (2022/02/01)
Specific intervention of senescent cells (SnCs) is emerging as a powerful means to counteract aging and age-related diseases. Canonical methods are generally designed to target SnC-associated signaling pathways, which are however dynamically changing and highly heterogeneous in SnCs, significantly limiting the effectiveness. Here, we present a tailor-made molecular prodrug targeting lysosome dysfunction, a unique feature shared by virtually all types of SnCs. The prodrug comprises three modules all targeting the altered lysosomal programs in SnCs, namely, a recognizing unit towards the elevated lysosome content, a linker cleavable by the activated lysosomal enzyme, and a lysosomotropic agent targeting the increased lysosomal membrane sensitivity. This spatially confined design enables killing broad-spectrum SnCs, with high specificity over non-SnCs. Along with in vivo benefits, this work offers a way to significantly expand the applicability of senotherapy in a wide range of diseases.
